Chemical and other procedures will be utilized to investigate the structures and functional characteristics of three protein systems. Studies of a membrane-derived form of galactosyl-transferase, which binds to and is activated by phospholipids will be extended to sequence analysis and the delineation of its multiple binding sites. The structure of human serum transferrin will be completed and the binding site for metals and ions and its receptor investigated. A recently discovered Ca2 ion pump from Golgi membranes that utilizes 3'5' cyclic AMP, but not ATP, will be subjected to characterization with respect to its enzyme properties, physiological significance and the nature of its polypeptide components.